Yes, that could be it. Google has made the Gmail version that has the proper Active Sync available to more phones then just the Nexus. They did it a few months ago. I can now get in on my Motorola Droid Turbo 2 but I didn't have it available to me when I first purchased my DT2. However, one may still has to MANUALLY CONNECT the Exchange account in the Gmail app as for me If I tried to simply enter in my email address and password it would default to IMAP meaning not contact sync.
That said, the phone manufacturers have the final say on what version of the Gmail app is available. Not sure if Samsung will allow the Active Sync version of the Gmail app on your phone.
I also read somewhere that even if your phone manufacturer won't permit you to install the proper Gmail version, one can still side load the APK and make their Gmail app active sync compatible.
See this link: (Note I can't verify the accuracy, but I have seen this info in more than one place)
http://forums.androidcentral.com/ne...ove-exchange-services-apk-6p.html#post5180928
In any case, this is EXTREMELY confusing for the end user. In my opinion, if Google want's to be taken seriously, then they need to settle their difference with Microsoft and bake Active Sync into core Android so that EVERY APP on the phone can centrally use it. That is what Apple does with IOS.
I imagine that this involves a royalty payment to Microsoft which could be why they don't do it.
In any case, SHAME ON GOOGLE. And/or Microsoft for making this so confusing to end users.
Oh, one final note. I was trying to help a family member out with their Galaxy S4 to get their contacts to sync properly with hotmail/outlook.com -- And I couldn't get it work correctly even though I was able to install the proper Gmail. I also was having trouble getting a Windows phone stock contact app to sync correctly with Gmail account -- and couldn't do it.
Like I said earlier -- SHAME ON GOOGLE AND/OR MICROSOFT for not working this out. There is no excuse for this, as both companies are EXTREMELY PROFITABLE. Have to hand it to the Apple folks, as IOS integrates this stuff far cleaner.